I have a purple Arum growing in the front garden and up until this year it has flowered every year giving me a beautiful purple bloom every year. This year it flowered and was yellow, then turned to seed. How do I go about saving this seed, as the head is now very heavy and the seeds are still green?
Callas can indeed be grown from seed. Once seed development begins, the flower fades. You will notice the “bumps” on the calyx enlarging; the weight will begin to pull the stem to the ground. This is normal. In time the seed capsules will begin to turn yellow and become mushy to the touch. It appears it's beginning to "rot" but this is all part of the process. At this point, the seed are mature, and each capsule contains at least one or two seeds, each resembling a miniature tuber, about 2 mm in size. Harvesting the seed is a bit messy; just gently squish out the individual seeds. Plant the seed 1/4" deep, space them about 1/2" apart. Cover lightly, and keep them warm, well lit & moist. Germination is erratic, and could take several weeks. Transplant after they've grown two or three leaves. Under optimum growing conditions, you might get a bloom in the second year; otherwise, expect something in the third year.